This invention relates generally to gas turbine engines, more particularly to combustors used with gas turbine engines.
Known turbine engines include a compressor for compressing air which is suitably mixed with a fuel and channeled to a combustor wherein the mixture is ignited for generating hot combustion gases. The gases are channeled to at least one turbine, which extracts energy from the combustion gases for powering the compressor, as well as for producing useful work, such as propelling a vehicle.
To support engine casings and components within harsh engine environments, at least some known casings and components are supported by a plurality of support rings that are coupled together to form a backbone frame. The backbone frame provides structural support for components that are positioned radially inwardly from the backbone and also provides a means for an engine casing to be coupled around the engine. In addition, because the backbone frame facilitates controlling engine clearance closures defined between the engine casing and components positioned radially inwardly from the backbone frame, such backbone frames are typically designed to be as stiff as possible.
At least some known backbone frames used with recouperated engines, include a plurality of beams that extend between forward and aft flanges. Because of space considerations, primer nozzles used with combustors included within such engines are inserted radially through a side of the combustor. More specifically, because of the orientation of such primer nozzles with respect to the combustor, fuel discharged from the primer nozzles enters the combustor at an injection angle that is approximately sixty degrees offset with respect to a centerline axis extending through the combustor. Accordingly, because of the orientation and relative position of the primer nozzle within the combustor, the primer nozzle is exposed to the combustor primary zone and must be cooled. Moreover, at least some known primer nozzles include tip shrouds which are also cooled and extend circumferentially around an injection tip of the primer nozzles. However, in at least some known primer nozzles, the cooling flow to the tip shrouds is unregulated such that if a shroud tip burns off during engine operation, cooling air flows unrestricted past the injection tip, and may adversely affect combustor and primer nozzle performance.